ArmVirtPkg: remove unused files

We no longer use ELF PIE executables to implement the self-relocating
PrePi so drop the custom linker script and visibility override header
file.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Sami Mujawar <Sami.Mujawar@arm.com>

ArmVirtPkg/Include/Platform/Hidden.h

@@ -1,22 +0,0 @@
-/** @file
-
-  Copyright (c) 2018, Linaro Limited. All rights reserved.
-
-  SPDX-License-Identifier: BSD-2-Clause-Patent
-
-**/
-
-#ifndef __PLATFORM_HIDDEN_H
-#define __PLATFORM_HIDDEN_H
-
-//
-// Setting the GCC -fvisibility=hidden command line option is not quite the same
-// as setting the pragma below: the former only affects definitions, whereas the
-// pragma affects extern declarations as well. So if we want to ensure that no
-// GOT indirected symbol references are emitted, we need to use the pragma, or
-// GOT based cross object references could be emitted, e.g., in libraries, and
-// these cannot be relaxed to ordinary symbol references at link time.
-//
-#pragma GCC visibility push (hidden)
-
-#endif

ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds

@@ -1,41 +0,0 @@
-/** @file
-
-  Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR>
-
-  SPDX-License-Identifier: BSD-2-Clause-Patent
-
-**/
-
-SECTIONS
-{
-  PROVIDE(__reloc_base = .);
-
-  . = PECOFF_HEADER_SIZE;
-  .text : ALIGN(CONSTANT(COMMONPAGESIZE)) {
-    *(.text .text*)
-    *(.got .got*)
-    *(.rodata .rodata*)
-    *(.data .data*)
-    *(.bss .bss*)
-
-    . = ALIGN(0x20);
-    PROVIDE(__reloc_start = .);
-    *(.rel .rel.*)
-    *(.rela .rela.*)
-    PROVIDE(__reloc_end = .);
-  }
-
-  .note (INFO) : { *(.note.gnu.build-id) }
-
-  /DISCARD/ : {
-    *(.note.GNU-stack)
-    *(.gnu.hash)
-    *(.gnu_debuglink)
-    *(.interp)
-    *(.dynamic)
-    *(.dynsym)
-    *(.dynstr)
-    *(.hash)
-    *(.comment)
-  }
-}